Too bad you don't have a newer version of SAS, because the LINES option and SLICE statement in GLIMMIX do exactly what you want! If you are in education or noncommercial activity, you can always install SAS University Edition (it is free),. and it is always the newest version. But that would take a while for you to learn about. With only 9.1, the table of mean differences you showed would have to be translated by you, by hand, into the letter (lines) display. You sort the means from high to low (or low to high), and then figure out which ones are different (different letters) and which ones are the same using the difference table. This can be tedious and take a while. You have an alternative that I think (?) should work in 9.1 (not absolutely sure). You can use the macro written by Hans-Peter Piepho. See the article here. You would need to download the macro and run it first (every time you launch SAS for the mean separation analysis). Then you follow the directions in the article to get the letter display. Note that you have to use the ODS output statement to save LSMEANS and mean differences from a MIXED run. With the interaction, you do slices of one factor at fixed values of the other. Good luck.(By the way, the macro can also do things not possible with the LINES option in current versions of SAS, but that is not relevant for your application). http://agrobiol.sggw.waw.pl/~cbcs/articles/CBCS_7_1_2.pdf You do need PROC IML for the macro to work.
Message was edited by: Larry Madden
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